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71.
背景:组织工程是一个多学科研究的交叉学科,其目标是使人体损伤的组织和器官再生,通过这种假设,几乎所有的动物组织都可以在实验室进行培养。一般的方法是从需要移植的患者身上提取干细胞,在一定的支持条件下允许其生长、增殖、生产为可替换的组织。另一方面,寻找细胞能够互相联结并形成分层结构的合适的支持条件,如基质或支架等非常必要。目前用于烧烫伤治疗的材料有很多种,如胶原,透明质酸、纤维蛋白和聚乳酸及其共聚物。
目的:讨论以新型的生物材料自体血浆为支架对自体成纤维细胞和角质化细胞生长、扩张、增殖的影响。
设计:建立一种真皮再生的方法,将自体成纤维细胞浸于人血浆基质中,排除各种影响样本安全性和排斥反应的问题,应用同样的方法在新的真皮上获取角质化细胞。
时间及地点:实验于2008年在意大利曼多瓦C. Poma医院动物工厂完成。
材料:人角质化细胞和成纤维细胞取自1例58岁乳房切除患者的皮肤碎片。实验得到C. Poma医院独立伦理委员会批准,患者知情同意。
方法:从自体活组织皮肤样本中分离人角质化细胞和成纤维细胞,置于培养瓶中增殖,随后将自体血浆作为皮肤移植形成构造的支架,免疫和免疫组织化学特征显示与正常皮肤相似。
主要观察指标:将血浆样本用甲醛固定,埋入石蜡,苏木精-伊红染色,用显微镜进行细胞计数。所有样本均经免疫组织化学评估。
结果:在血浆基质上获得了多层规则形状的角质化细胞和成纤维细胞,基底膜的形成说明自体血浆是角质化细胞和成纤维细胞的生长、分化、扩展的良好支架,真皮和表皮细胞联结重建皮肤移植与正常皮肤无异。
结论:血浆作为角质化细胞和成纤维细胞分化、扩展的支架表现出良好的性能,同时实验还特别发现成纤维细胞浓缩血浆可以暂时替代皮肤,也是角质化细胞生长的强有力的支架。此外血浆还具有廉价,易于制备等优点。自体角质化细胞和成纤维细胞及自体血浆的应用,可以避免血种类型的免疫排斥反应。这种治疗方法给有慢性缺损并且需要连续移植的患者带来了希望。
doi:10.3969/j.issn.1673-8225.2009.47.001 相似文献
72.
73.
Abstract: Juvenile xanthogranuloma is a benign histiocytic skin disorder encountered primarily in infancy and childhood. Approximately 0.4% of cases exhibit ocular manifestations, which can result in glaucoma and blindness. We present a case of a 7-month-old male with unilateral glaucoma associated with Juvenile xanthogranuloma, and emphasize the importance of an ocular screening in patients with Juvenile xanthogranuloma, especially those with periocular lesions. 相似文献
74.
自制32P敷贴器治疗瘢痕疙瘩 总被引:1,自引:0,他引:1
目的:观察自制32P敷贴器局部敷贴治疗不同类型瘢痕疙瘩的临床疗效。
方法:105例瘢痕疙瘩患者中,39例病变厚度≤ 0.3 cm的行单纯敷贴治疗,病变厚度> 0.3 cm的66例随机分为2组,单纯敷贴组36例,手术+敷贴组30例。单纯敷贴根据病变表面积大小及形状剪取敷贴片,根据剂量率和衰变校正计算每天敷贴时间,直接贴于病变表面,每天4.0~5.0 Gy/(部位•次),连续4 d为一疗程,每疗程间隔4周,总治疗4~6个疗程。幼儿单次剂量控制在每天4 Gy/(部位•次)以下。手术+敷贴组患者手术切除瘢痕疙瘩,待手术伤口无渗出后根据伤口形状剪取敷贴片对准伤口敷贴,剂量及疗程同单纯敷贴组。
结果:单纯敷贴治疗对病变厚度≤0.3 cm的39例瘢痕疙瘩治愈32例(82%),总有效率98%;对病变厚度> 0.3 cm的瘢痕疙瘩单纯敷贴和手术+敷贴两组治疗总有效率分别为56%和93% ,两组差异有显著性意义(P < 0.01),其中病程< 9个月的患者治疗有效率分别为25%和75%,病程较长患者治疗有效率分别为13%和77%。治疗过程中有26例在敷帖过程中出现局部皮肤烧灼和刺痛感,均以炉甘石洗剂局部外用处理后缓解;5例出现Ⅰ度放射性皮炎,2例出现Ⅱ度放射性皮炎,以百多邦软膏局部外用后缓解,无出现Ⅲ度以上放射性皮炎病例。治愈患者局部皮肤均有不同程度的色素沉着或皮肤颜色改变。
结论:32P敷贴治疗瘢痕疙瘩治疗安全有效,对病程较短或病变厚度小于0.3 cm的患者可单纯敷贴治疗,病程较长或病变厚度大于0.3 cm患者建议先手术后再敷贴治疗。 相似文献
75.
背景:与小肠黏膜下层等材料相比,脱细胞血管具有天然管状结构,与输尿管形态结构相近,替代输尿管时仅需端端吻合即可,手术操作简单,血管外壁光滑,获取及制备方法简便等优点。
目的:拟应用同种颈动脉血管无细胞基质体外构建输尿管。
设计、时间及地点:观察性实验,于2006-09/2008-06在上海交通大学医学院附属新华医院动物实验中心完成。
材料:长风杂交白猪由上海松联实验动物公司提供。上海交通大学医学院实验动物中心提供的健康成年大鼠8只,用于血管无细胞基质的动物毒性实验。
方法:剥去猪颈动脉血管外膜,PBS冲洗若干遍,然后将血管置于pH 7.1 的PBS中4 ℃下振荡清洗,0.5%十二烷基硫酸钠振荡24 h,后使用双蒸水4 ℃下反复振荡洗涤1周,每日换双蒸水2次。对于解剖过程中肌肉残留相对稍多的血管,在双蒸水洗涤前以混合消化液37 ℃下振荡消化约2 h,再行双蒸水洗涤。制备的无细胞基质置于青、链霉素溶液中,4 ℃保存,完成脱细胞支架制备。
主要观察指标:光镜及电镜观察脱细胞后管壁无细胞基质片的主要成分。将同种异体来源内皮祖细胞培养增殖后植入血管无细胞基质,观察细胞生长情况,并进行血管无细胞基质动物毒性实验。拉力实验了解血管无细胞基质材料的收缩性能。
结果:颈动脉血管无细胞基质中已无细胞成分,无细胞基质主要由胶原成分组成。扫描电镜未见该材料表面存在细胞及细胞碎片,同时发现该无细胞基质存在孔隙样结构。体外同种异体来源的内皮祖细胞培养增殖后植入血管无细胞基质,细胞黏附于无细胞基质。血管无细胞基质按毒性分级属于无毒级。拉力实验说明该无细胞基质具有一定的韧性和牵张性。
结论:采用胰酶和十二烷基硫酸钠制备的颈动脉血管无细胞基质材料无细胞残留,具有一定的韧性和牵张性,种植于其中的种子细胞具备一定的生长能力。 相似文献
76.
77.
78.
H. J. J. Kars Juha M. Hijmans Jan H. B. Geertzen Wiebren Zijlstra 《Journal of diabetes science and technology》2009,3(4):931-943
The objective of this review is to identify and review publications describing the impact of reduced somatosensation on balance. Based on knowledge of the association between specific somatosensory loss and deterioration of balance, conclusions can be made about role of somatosensation in standing balance.A systematic literature review is presented in which publications from the years 1993 through 2007 were searched in Medline and Embase. Medical Subject Headings (MESH) terms and free text words (related to balance, somatosensory loss, and lower limb) were used to perform the searches. Fifteen articles were selected for detailed review based on predetermined inclusion criteria, and three of the included articles described the effect of experimentally reduced somatosensation on balance in healthy subjects. Ten of the articles described balance in diabetic neuropathy (DN). The last two included articles described balance in Charcot-Marie-Tooth (CMT) disease type 1A (CMT1A) or type 2 (CMT2).The literature indicates that the tactile sensation is reduced in DN, CMT1A, and CMT2 and when the plantar surface of the feet was hypothermically anesthetized. Joint motion sensation seems to be impaired in patients with DN, and passive joint position sensation appears to be reduced in healthy subjects with anesthesia of ankle and foot from prolonged ischemia. This reduced somatosensation seems to have a negative effect on balance in patients with DN and CMT2; however, this appeared not to be the case in patients with CMT1A and in healthy subjects. 相似文献
79.
Background: The term 'pigmented epithelioid melanocytoma (PEM)' was recently used for borderline melanocytic tumor/low-grade melanoma including cases previously diagnosed as human animal-type melanoma and epithelioid blue nevus. No Japanese cases have been reported.
Methods: We reviewed 219 cases previously diagnosed as blue nevus in Japan. Common blue nevus was identified in 154 cases and cellular blue nevus in 65 cases.
Results: We have found two Japanese cases of PEM previously diagnosed as cellular blue nevus. Two patients were female. The age at presentation was 32 and 28 years. Two lesions were on the buttock. Two cases fulfilled histological criteria proposed for PEM. There is no evidence of recurrence or metastases.
Conclusions: PEM is a distinct melanocytic tumor and the unifying diagnostic term. PEM is present in Japanese, but these cases may be previously diagnosed as cellular blue nevus. Japanese pathologists should recognize a new concept of PEM, and when they make a diagnosis of PEM, they should be recommended sentinel lymph node sampling. 相似文献
Methods: We reviewed 219 cases previously diagnosed as blue nevus in Japan. Common blue nevus was identified in 154 cases and cellular blue nevus in 65 cases.
Results: We have found two Japanese cases of PEM previously diagnosed as cellular blue nevus. Two patients were female. The age at presentation was 32 and 28 years. Two lesions were on the buttock. Two cases fulfilled histological criteria proposed for PEM. There is no evidence of recurrence or metastases.
Conclusions: PEM is a distinct melanocytic tumor and the unifying diagnostic term. PEM is present in Japanese, but these cases may be previously diagnosed as cellular blue nevus. Japanese pathologists should recognize a new concept of PEM, and when they make a diagnosis of PEM, they should be recommended sentinel lymph node sampling. 相似文献
80.
Nand L. Sharma Vikram K. Mahajan Neelam Gupta Nitin Ranjan and Anju Lath 《Journal of cutaneous pathology》2009,36(4):486-492
Ehlers-Danlos syndrome – vascular type, the only lethal form, is rarely reported in dermatology literature. It is characterized by translucent, atrophic skin, easy bruising, arterial, intestinal and/or uterine fragility manifesting as varicose veins, aneurysms and vascular/visceral/uterine rupture. As its dermatopathologic features are not well elucidated, diagnosis is often made after a catastrophic complication or at autopsy. This 36 year-old non-consanguineous male had brown-black plaques with atrophy and frequent ulceration over legs and dorsal feet and tortuous varicose veins around ankles for the past 15 years. Perivenous skin was translucent and hypopigmented. He had multiple and ecchymotic keloids and small atrophic, pityriasis versicolor-like lesions over trunk. He did not have hypermobile/hyperextensible skin and joints and showed no systemic or investigative abnormality. Histopathologic features of atrophic lesion included blood extravasation in atrophic epidermis/dermis, focal clustering and dilatation of blood vessels, malformed vessel walls, abundant hemosiderin in the dermis and homogenously stained/whorled patterned collagen especially around blood vessels. Pathology of keloidal lesion showed new collagen and vascular fragility. These histopathologic features appear of diagnostic value especially in patients who have compatible clinical findings but cannot afford confirmation by biochemical testing for abnormal synthesis of type III procollagen or identification of mutations in the COL3A1 gene. 相似文献